• Journal of the Korean Chemical Society
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• v.42 no.3
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• pp.302-305
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• 1998

The high cholesterol level in the blood stream is the main cause for cardiovascular diseases. Despite considerable worldwide effort to reduce the blood cholesterol level, we still need a remarkable drug. For this reason, the inhibition of cholesterolesterase by synthetic porphyrin complexes was investigated. Some of the phenyl substituted porphyrins inhibited the enzyme and the inhibition constant was in the range of ${\mu}M$. The substituents on the phenyl group of tetraphenylporphyrin did not affect much on the inhibition constant.

• Korean Journal of Plant Resources
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• v.31 no.5
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• pp.423-432
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• 2018

This study was performed to develop a new natural antimicrobial materials by analyzing the effect of extracts obtained from Ten Lauraceae Species on the inhibitory activity against Propionibacterium acnes. The plant materials were collected from Wando and Jeju islands, and the antimicrobial activity of the crude extracts was examined by the agar diffusion method with different part (i.e., leaf and branch), solvents (i.e., distilled water, 80% ethanol, and 100% methanol) and at different ultrasonic extracting times (i.e., 15, 30, and 45 minutes). The control agents used were synthetic antimicrobials, methylparaben and phenoxyethanol, at concentrations of 0.4, 1, 2, and 4 mg/disc. Altogether, extracts of 10 species used in the study showed inhibitory activity, which confirmed their antimicrobial action against acnes. Among these, leaves of Laurus nobilis L. which was extracted in 80% ethanol for 45 min showed the largest clear zone (19.8 mm). Leaves of L. nobilis L., showing highest antimicrobial activities among 10 species, were successively reextracted with n-hexane, chloroform, ethylacetate and n-butanol. As a results, in all fractions except butanol, clear zone above 10 mm were formed. The ethyl acetate fraction showed the highest inhibitory activity (13.3 mm) and the inhibitory activity was significantly higher than that of crude extract (10.2 mm) and phenoxyethanol as a control (12.5 mm).

• Applied Biological Chemistry
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• v.51 no.1
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• pp.49-54
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• 2008

The concentration of total phenolic compounds of the water extracts and 80% ethanol extracts form Portulaca oleracea were 3.05 ${\mu}g/ml$ and 6.33 ${\mu}g/ml$, respectively. The total antioxidant activities of water extracts and 80% ethanol extracts of Portulaca oleracea were 89.2% and 72.9% in DPPH assay, 69.0% and 96.5% in ABTS assay, antioxidant protection factor of the water and 80% ethanol extracts were each 2.73 PF and 3.63 PF. Tyrosinase inhibitory activities were water extracts and 80% ethanol extracts of Portulaca oleracea were 20.2% and 38.7%. Portulaca oleracea showed high antimicrobial activites against Helicobater pylori, Staphylococcus epidermidis, Staphylococcus aureus, Eschericia coli and Streptococcus mutans. Minimum inhibitory concentrations (MICs) on Helicobacter pylori, Staphylococcus epidermidis, Staphylococcus aureus, Escheichia coli and Streptococcus mutans were 200, 50, 100, 100 and 150 ${\mu}g/ml$, respectively. The result suggest that Portulaca oleracea extracts may be useful as potential source as antioxidant and antimicrobials.

• Korean Journal of Plant Resources
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• v.23 no.5
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• pp.436-444
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• 2010

Methanol extracts of the aerial and rhizome parts obtained from ten species of ferns has been screened for antimicrobial activities against Bacillus subtilis, Escherichia coli, Listeria monocytogenes, Propionibacterium acnes, Streptococcus mutans and Streptococcus sobrinus. Antimicrobial activities were carried out using broth microdilution method and paper disc diffusion assay and the extracts which showed clear zones more than 15mm in concentration of 2 mg/disc were tested for its antimicrobial activities at the $0.125{\sim}2\;mg{\cdot}mL^{-1}$ concentration of each extract for three days. The non-sterilized crude methanol extracts of Osmunda cinnamomea var. fokiensis rhizome showed the highest antimicrobial activities on B. subtilis(39%), E. coli (33%) and L. monocytogenes(58%) at the concentration of $2\;mg{\cdot}mL^{-1}$ after 72 hours. In P. acnes, frond extract of O. cinnamomea var. fokiensis showed most vigorous antimicrobial activities in the all extracts but it showed weak activity(clear zone diameters below 15 mm). All extracts has the antimicrobial activities on Streptococcus, but they exhibited weak activity. At the concentration of $2\;mg{\cdot}mL^{-1}$, only Osmunda japonica rhizome extracts showed 28 and 39% of antimicrobial activities on S. mutans and S. sobrinus after 72 hours and the other extracts showed below 10% of antimicrobial activities on S. mutans and S. sobrinus.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.214-220
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• 2019

Hwangryunhaedok-tang (HT) is prescribed in oriental medicine to treat inflammation-related diseases. This study examined the anti-bacterial effect to select the index components of Traditional Chinese Medicine (TCM) HT. The disc diffusion method and minimum inhibition concentrations (MIC) tests were conducted to measure the antibacterial activity of HT. The strains were Staphylococcus aureus ATCC 25923 and Escherichia coli 23724. Berberine and geniposide were selected as the index components of HT and were analyzed quantitatively by high-performance liquid chromatography (HPLC). As a result, the inhibition ring was formed at $11.7{\pm}1.3mm$ and $8.7{\pm}0.7mm$ at HT 20 mg and 10 mg on S.aureus ATCC 25923, respectively; and $8.0{\pm}0.0mm$ at HT 20 mg on E.coli ATCC 23724. The MIC were 31.25 mg/mL in S.aureus ATCC 25923 and 125.0 mg/mL in E.coli ATCC 23724. In quantitative analysis for standardization, HT contained 16.55 mg/g of berberine and 81.85 mg/g of geniposide. Overall, when antibiotics are developed using natural products, they may reduce the side effects and inhibit resistant bacteria. If research on HT continuously proceeds, positive developments are expected to be made in oriental medicine as well as in various other industries.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.17-19
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• 2004

트렌치 게이트 구조를 통해 순방향 전압 강하 손실 없이 기생 사이리스터 래치-업을 억제시키는 새로운 수평형 절연 게이트 바이폴라 트랜지스터 (LIGBT)를 제안하였다. 제안된 소자의 베이스 션트 저항은 정공의 우회로 인하여 감소하였으며, 이에 따라 기생 사이리스터 래치-업이 억제되었다. 제안된 소자의 순방향 전압강하는 트렌치 구조에 의한 유효 채널 폭 증가로 감소하였다. 제안된 소자의 동작 원리 분석을 위해 ISE-TCAD를 이용한 3차원 시뮬레이션을 수행하였으며, 표준 CMOS 공정을 이용하여 소자를 제작 및 측정하였다. 제안된 소자의 순방향 전압 강하는 기존의 LIGBT에 비해 증가하지 않았으며, 래치-업 용량은 2배로 향상되었다. 제안된 소자의 포화 전류는 감소하였으며, 이로 인하여 소자의 강인성 (ruggedness)이 향상되었다.

• Journal of Food Hygiene and Safety
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• v.2 no.1
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• pp.35-40
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• 1987

The antilipidperoxidative effects of Brazilin and Hematoxylin were investigated at the levels of liver~total homogenates, -microsomal fraction, -mitochondrial fraction and the sera of SD-rats intoxicated with $CCl_4$ and ethanol. Both natural dyes markedly inhibited the lipidperoxidation induced by $CCl_4$ and ethanol. Brazilin and Hematoxylin showed the inhibitory effects on the both enzymatic (NADPH-dependent) and nonenzymatic (Ascorbate-induced) lipidperoxidation pathways. but it is supposed that the antilipidperoxidative powers of them mainly result from the inhibition of the nonenzymatic lipidperoxidation.

• The Science & Technology
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• v.29 no.9 s.328
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• pp.32-33
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• 1996

1972년 창립된 한국인구학회는 그동안 정부의 인구억제정책의 입안과 실시에 학문적으로 뒷받침해 한국경제의 고도성장에 크게 이바지했다. 현재 3백여명의 회원을 두고 있는 한국인구학회는 매년 두차례 정기학술발표회를 개최하고 있으며 연2회 기관지를 발행하는 등 광범한 학술활동을 계속해 오고 있다.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.10a
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• pp.16-16
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• 2010

본 연구는 13과 37종 양치식물의 엽상체(지상부)와 근경의 메탄올 추출물을 대상으로 식품의 오염 및 변질의 원인이 되는 Bacillus subtils, 식중독의 원인이 되는 Escherichia coli, 식중독 및 선회병(listeriosis)의 원인이 되는 Listeria monocytogenes, 피부 여드름의 원인이 되는 Propionibacterium acnes에 대한 항균활성을 탐색하고 항균력이 우수한 천연소재를 선발하기 위하여 시행하였다. $5mg{\cdot}mL^{-1}$의 농도의 추출물을 대상으로 각 미생물에 대하여 50% 이상의 항균활성을 나타낸 양치식물 추출물을 선발하였으며, 선발된 추출물을 2mg/disc의 농도로 조절하여 agar diffusion법으로 항균력을 측정하여 15mm 이상의 억제환을 나타내는 추출물을 선발하였다. 상기의 방법으로 선발된 추출물을 $0.125{\sim}2.000mg{\cdot}mL^{-1}$의 농도로 조절하여 72시간 동안 각 미생육의 생육에 미치는 영향을 분석하여 항균활성이 우수한 양치식물의 추출물을 선발하였다. 연구의 결과, B. subtils의 생육억제에는 야산고비의 성엽과 쇠고비의 근경 추출물, E. coli의 생육 억제에는 설설고사리의 성엽과 나도히초미 및 더부살이고사리의 근경 추출물, L. monocytogenes의 생육억제에는 관중의 성엽과 공작고사리, 꿩고비 및 쇠고비의 추출물이 효과적이었다. 한편 대부분의 양치식물 추출물은 P. acnes의 생육억제 효과가 미비하였으나, 관중과 참지네고사리는 성엽과 근경 모두에서 P. acnes의 생육억제 효과가 매우 우수하였으며, 별도의 제균처리를 하지 않은 관중과 참지네고사리의 메탄올 조추출물의 $MIC_{50}$은 성엽의 추출물에서 66.8과 $80.4{\mu}g{\cdot}mL^{-1}$, 근경의 추출물에서는 8.8과 $54.2{\mu}g{\cdot}mL^{-1}$로 나타났다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1587-1594
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• 2010

This study was designed to investigate the effect of Artemisia capillaris extracts on the intestinal microflora. In agar diffusion method, the solvent fractions of Artemisia capillaris showed growth inhibition against the intestinal microflora. In particular, the chloroform fraction of Artemisia capillaris had strong antibacterial activity against Clostridium perfringens, Clostridium difficile, Eubacterium limosum, and Bacteroides fragilis, but did not show antibacterial activity against Bifidobacterium bifidum and Lactobacillus acidophilus. Most chloroform fraction of Artemisia capillaris inhibitory activities were not reduced by heat treatment or pH variation against C. perfringens, C. difficile, E. limosum, and B. fragilis. MICs of the chloroform fraction were 1.25 mg/mL against C. perfringens, E. limosum and B. fragilis and 2.5 mg/mL against C. difficile. MBCs of chloroform fraction were 5 mg/mL against C. perfringens, E. limosum and 2.5 mg/mL against C. difficile, B. fragilis. The ethyl acetate fraction of Artemisia capillaris showed $3.08{\pm}0.03$ mg/10 mg total polyphenol and $1.91{\pm}0.03$ mg/10 mg total flavonoid contents. In vivo tests were performed to investigate the influence of Artemisia capillaris extract on the intestinal microflora in rats. The results showed the possibilities of utilizing Artemisia capillaris extracts as a functional food component to control intestinal microflora.